A blower wheel with forward curved blades is commonly found in a wide variety of air moving applications. These may include residential furnaces and air handlers as well as larger commercial heating and air conditioning systems. The fans are typically driven by an electric motor that can be coupled either directly to the motor shaft (direct drive), or through a system of sheaves and belts (belt drive).
The coupling from the motor to the fan occurs at a central rotating disk, or centerdisk, that contains a means to secure the motor shaft and transmit motive force to the fan blades. The centerdisk is often composed of two formed parts that are nested together to create the centerdisk assembly. A hub containing a set-screw, for attachment to the motor shaft, is fastened into the centerdisk.
Due to structural constraints and the need to access the set-screw with a tool a large washer is placed between the two centerdisk parts to provide structural stiffness and clearance to access the set-screw.
Representative of the art is U.S. Pat. No. 4,329,118 (1982) A line of forwardly curved blower wheels of different diameters incorporates blades of the same angular extent in all wheels but with the radii of curvature of the individual blades proportional to the diameter of the wheel wherein they are incorporated. In addition, the center disks of the double inlet wheels and the end plates of the single inlet wheels are provided with novel mounting structure comprising segments bent out of the plane of the disk or end plate and secured to opposite ends of the hub member by which the wheel is mounted on a shaft, and the individual blades are retained in complementary slots in the disk or plate and fillet welded to the disk or plate respectively.
What is needed is a blower wheel comprising a blower wheel comprising a centerdisk comprising a conical portion, a planar portion for receiving a hub, and an arcuate portion intermediate the conical portion and an outer portion. The present invention meets this need.